subject: Economical Alternative To Hard-grinding Tools And Technology Vehicles [print this page] Research has confirmed that in the hard ground surface has a car and whitening layer. Although they are usually associated with the surface residual stress, but may also indicate that whitening layer of residual stress. In any case, whitening layer causes and they have not fully understand the workpiece.
Some studies recommend the use of cutting fluid helps eliminate bleaching layer, while others show no effect of cooling fluid. There is some evidence of cutting tools for effect bleaching layer was formed. In general, more likely to produce new non-destructive tool surface layer increases with whitening tool wear increases. This may be caused by friction between the tool and the workpiece caused by the heat generated caused by flank wear increases, or increased friction caused by the higher plastic deformation.
New tools and techniques to reduce processing time for up to 90%
In recent years, hard truck parts 'unknown' surface integrity also caused some reluctance to hard turning as a key to surface finishing. However, the recent development of tool technology is likely to challenge these ideas. In particular, the new overall PCBN inserts and insert new car technology has been proven to be quite traditional grinding or better accuracy.
One recent development in Elephant and CBN300 such high CBN100 cars finishing on the hard economic choices of the overall high PCBN inserts. Specifically for the overall process of hardened steel blade CBN100 and CBN300 provide and traditional or carbide tipped blade the same number of cutting edge, plus a long cutting edge. Due to their overall structure, the new blade to provide significantly higher wear resistance and lower the cost per blade. The high mountains in a whole blade knives with other five different manufacturers tipped blade comparison study, each edge of cost savings from 25% to 208% range.
As additional advantages, CBN100 and CBN300 also makes it possible to insert car. Insert is a used car or part of the cutting edge cutting edge to create a right angle cutting of hard turning the form of high productivity. This relatively new technology has been proven to reduce processing time by up to 90%, production of those parts of surface grinding with the same integrity.
Grinding or hard turning parts of the most critical feature is the size (diameter), roundness, straightness, bearing area, surface roughness and residual stress. For the first four features, for a large ring gear or bearing car can easily be inserted the following accuracy.
Diameter + /-0.0006in. (0.015mm)
Roundness + /-0.00015in. (0.004mm)
Straightness + /-0.00015in> (0.004mm)
Bearing area of 90% deep (0.00008in. 0.002mm)
Generating a continuous tradition of turning grain Road, the surface finish mainly on the nose radius, feed rate, cutting speed and cutting depth. Instead, insert car parts surface quality depends on the quality of the cutting edge. As a result, car parts inserted in the axial display low residual stress, and the sealing properties and the same or better than grinding surface.
Use whole PCBN inserts, these stress patterns remain constant, even when such a large number of production. Plug in a test vehicle parts 250 physical properties of tests, found significantly lower than the grinding residual stress caused by stress. Parts quality is also affected by the tangential residual stress distribution. In another test of 250 parts, the grinding and insert cars in the surface residual tensile stress, but car parts in the plug on the thickness of the affected zone is clearly thinner.
Also found to reduce bleaching layer insert car occurred, because it reduces the cutting edge on the flank wear due to the surface of each processing shorter cutting time. It also produces lower cutting forces and less friction, resulting in less heat delivered to the workpiece surface.
Although often regarded as hard turning method much more expensive than traditional finishing, the recent development of tools and technologies are gradually changing these values. With regard to surface finish and integrity required to meet the capacity of response to the question, hard turning finishing and good as an economic alternative to grinding of the program was more widely recognized. Greater flexibility, faster tool changes and longer tool life both on reducing processing costs, increase productivity and better quality parts role, far exceeding the initial cost of PCBN cutting tools.
